When consumers wash their clothes, they often want the fabric to come out looking clean and feeling soft. Conventional detergents often provide desirable stain removal and whiteness benefits, but washed fabrics typically lack the “soft feel” benefits that consumers enjoy. Fabric softeners are known to deliver soft feel through the rinse cycle, but fabric softener actives can build on fabrics over time, and can lead to whiteness negatives over time. Furthermore, detergents and fabric softeners tend to be sold as two different products, making them inconvenient to store, transport, and use. Therefore, it would be beneficial to formulate a single product that provides both cleaning and softness benefits.
However, formulating compositions that deliver both cleaning and softness benefits is a challenge to a manufacturer. Simply adding a softness benefit agent, such as silicone, to a conventional detergent is often ineffective, as the feel benefit agent tends to be washed away by the surfactant present in the detergent rather than depositing on clothes, resulting in an inefficient use of the feel benefit agent. Furthermore, increasing the level of the softness feel benefit agent to deposit sufficient silicone to impart a feel benefit does not necessarily solve this problem since a high level of feel benefit agent can cause stability problems in the final product.
Cationic deposition polymers can be used to increase deposition efficiency of silicones onto fabrics and the softness benefits that flow therefrom. However, it has been found that conventional silicone-containing detergents that comprise traditional deposition polymers, which typically have a high molecular weight, do not clean or maintain whiteness benefits as well as conventional detergents that do not contain the cationic deposition polymers. Without intending to be bound by theory, it is believed that traditional cationic deposition polymers deposit not just silicone, but also soils from the wash water onto fabric, resulting in dingy fabrics and/or losses on stain removal benefits. For example, traditional cationic polymers can flocculate clay, since the cationic polymers interact with the anionic surfactants in the detergent, leading to clay redeposition.
Therefore, there is a need for a single product that provides both good whiteness maintenance and good softness benefits. It has been surprisingly found that by selecting particular combinations of specific low-molecular-weight cationic deposition polymers and surfactant systems, it is possible to formulate a silicone-containing composition that provides such benefits.